Process for producing grinding-disks.



F. N. @L F. E. GARDNER.

PROCESS FOR PRODUGING GRINDING DISKS.

APPLICATION FILED APR. 25. 1908.

Patented Jan. 11, 1910.

l rovementsA in Processes for Producing y UNITED sTATEs PATENT oEEIoE.

FREDERICK N. GARDNER AND FREDERIC GARDNER, OF BELOIT, WISCONSIN, AS- SIGNORS OF ONE-THIRD TO LOUIS WALDO THOMPSON, OF BELOIT, WISCONSIN.

Specification of Letters Patent.

Patented Jan. 11, 1910.

Application filed April 25, 19 08. Serial No. 429,131.

the United States, residing at- Beloit, in thev county of Rock and State of lVisconsin, have invented certain new and useful Imrinding-Disks, of which the following is a s ecification. Y

his invent-ion relates to processes for producing abrasive disks adapted to be secured to the rotary disk 01 disks of disk inders.A Heretofore such abrasive disks ave been made by. placin(r liquid glue upon cloth, paper, or similar Ibacking material,

- and sprinkling or spreading granular abravFic.'

sixteenth vofan inch i sive material, such as emery or corundum, upon the glue, the abrasive material becoming fixed to the backing sheet when the glue hardened. In carrying out this process, the amount of abrasive material that can be at.- tached to the sheet is limited bythe amount of liquid glue that can be made to stand upon the sheet. Furthermore, the abrasive material does not settle and mix evenly throughout the glue upon which it is posited; consequently, as heretofore made.

such grinding disks are more free cutting and softer on the surface than they are after they have been used for a short time. As they wear doivn they cut less and less freely because the proportion of glue to abrasive material is excessive in the lower part of the layer of abrasive material. These considerations render impracticable the manufacture by former methods of grindingr disks v much thicker than oneand one-half or, atl most,^double the size `of .the grainsv of the abrasiven1aterial: for example. with No. 24 grain, `the diskvcan'not beniade over oneto one-twelfth of an inchV `in thickness'. i

Our improved process may compose the following steps'in thoroughly mixing a binding material anda granular abrasive material-"in proper proportions to produce a grinding disk of the required temper; spreading said mixture upon a sheet of cloth, paper, or other suitable backing material, which has been coated with just enough glue to cause the mixture to adhere firmly to the sheet; rolling the mixture into a layer of uniform thickness; tilting into cutting position the grains that Were caused by the rolling operation to lie with their faces l manufacture.

parallel to the face of the disk; and allowing the Whole to dry andv harden. It is evident that the thickness of the layer of abrasive material is limited only by the strength of the cement by means ofv which said layer and the backing sheet are united.

In the accompanying drawings, Figure 1 'is a sectional view of a machine that may be used in carrying out the process herein described. Fig. 2 is a view, partly in section, cfa roll that isuseful inv performing one step of the process. Fig. 3 is a fragmental sectional view of a grinding disk producedby our process.

In Fig. 1, 1 refers to a bench or table, and 2 to a mold mounted on said table, the diameter of the mold corresponding to the diameter of the disk grinder disk 3 to be made. Such disks ordinarily have a central opening 4 (Fig. 3l, to `define which a circular block 5 is fixed in the center of the mold 2. is a movable or false bottom in the mold, to support the disk during the process of meansof a spindle 7 slidably mounted in bearings 8 in a bracket 9 located beneath the bench or table 1, said spindle bearing at its upper end a crosshead 10 which is connected with the mold-bottom G by the pins 11. said the surface of the grinding disk. l5 is a u The bottom 6 is movable to v remove the grinding disk from the mold. by

member having a hub 1G which is rotatably mount-ed` upon the pivot 14, saidfmember" quantity of the mixture to till the mold is I lhavimgra-shaft .1T ixedtherein and'#carrying' :at its outer end a handle`1Sf'19is a smooth'v roll and 20 a` Atoothedfrollwhich -may lhe laced in said mold, and the mixture may be rolled with the roti E9 into a layer E23 of uniform thickness. This rolling coinpresses the mixture somewhat and presses it Into close contact with the film 22 of cement upon the backing sheet '21. Incidentally this rolling arranges substantially all of the grains at the surface of the layer of abrasive material with a tlat surface parallel to the face of the disk, which obviously is not the most eicieut cutting position of the grains. lVe therefore tilt the grains in any suitable wa after they have been rolled into a. flat ayer so as to dispose their cuttin edges toward the face of the disk, as indicated in Fig. 3. The tilting of the grains may be accomplished by means of the roll 20, said roll being substituted for the smooth roll 19 upon the shaft 1T. After the ains have :been tilted the member 15 is ifted olf the ivot 14 and laid aside, and the hand-wheel'l rotated to raise the grinding disk out of the mold 2. Said grinding disk is then removed and dried in any suit.- able way.

`The bond being i'nixed with the abrasive material bcft re the latter is placed upon the hacking sheet, it apparent that disks of mia-h greater thicknessl than those heretofore nmluccd can be made, and therefore that t ie life of our grinding disk is pro rtionately longer. l*`urthermore, our dis is of eren cutting quality from4 the time its use is begun miti] the abrasive material has been worn away, as the bond is uniformly distributed throughout the layer of abrasive.

Our improved process also permits of obtaining any desired variations in the proportion of bond to abrasive material, with consequent variations in temper or cutting Word in in the Patent Otlice.

in Letters Patent No. 945,931.

[SEAL] "disks for lt is hereby certified that in Letters Patent No. 945,931, granted January 11 of Beloit, Wisconsin, for an improvement in Page 1, line 43, for the word compose,

quality, a result not readily obtainable by the' processes ployed.

lt. will be observedthat a disk made in accordance with our invention requires, no cuttingor trimming.

Tilting the grains of abrasive material places the great. majority of them in position to do effective work.

le claim as our invention:

1. The process of producin grinding facing the sidesof te disks of disk grinders, which consists inthoroughly mixing a bond and a granular abrasive material, applying a thin coat of cement to a backing sheet, placing said mixture upon the coated surface of said backing sheet, placing the grains with their cutting edges in cutting position, and drying.

Q. The process of producing grinding disks for facing the sides of the disks of disk grinders, which consists in mixin a bond and a granular abrasive material, applyin a thin coat of cement to a backing sheet, p :icing said mixture upon the coated surface of said backing sheet, rolliner the mixture into a layer of uniform thickness, tilting the grains to dispose their cutting edges in cutting position, and drying. l

3. The ste in the process of producing grinding dis s for facing the sides of the disks of disk grinders, which consists in tilting the grains after they have been deposited, so that their cutting edges are directed toward the face of the disk.

FREDERICK GARDNER. FREDERIC E. GARDNER. Witnesses:

' T. D. WOOLSEY,

F. F. LiviiaMonn.

and certainly heretofore em- 1910,l upon the application of Frederick N. Gardner and Frederic E. Gardner,

Disks errors appear in the printed specification requiring correction as follows:

read comprise; same page, line 4.4, the

should be canceled; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case Signed and sealed this 31st day of March, D., 1914.

J. T. NEWTON,

Acting ommesoner of Patents.

Processes for Producing Grindinglaced in said mold, and the mixture may be rolled with the roti E9 into a layer E23 of uniform thickness. This rolling coinpresses the mixture somewhat and presses it Into close contact with the film 22 of cement upon the backing sheet '21. Incidentally this rolling arranges substantially all of the grains at the surface of the layer of abrasive material with a tlat surface parallel to the face of the disk, which obviously is not the most eicieut cutting position of the grains. lVe therefore tilt the grains in any suitable wa after they have been rolled into a. flat ayer so as to dispose their cuttin edges toward the face of the disk, as indicated in Fig. 3. The tilting of the grains may be accomplished by means of the roll 20, said roll being substituted for the smooth roll 19 upon the shaft 1T. After the ains have :been tilted the member 15 is ifted olf the ivot 14 and laid aside, and the hand-wheel'l rotated to raise the grinding disk out of the mold 2. Said grinding disk is then removed and dried in any suit.- able way.

`The bond being i'nixed with the abrasive material bcft re the latter is placed upon the hacking sheet, it apparent that disks of mia-h greater thicknessl than those heretofore nmluccd can be made, and therefore that t ie life of our grinding disk is pro rtionately longer. l*`urthermore, our dis is of eren cutting quality from4 the time its use is begun miti] the abrasive material has been worn away, as the bond is uniformly distributed throughout the layer of abrasive.

Our improved process also permits of obtaining any desired variations in the proportion of bond to abrasive material, with consequent variations in temper or cutting Word in in the Patent Otlice.

in Letters Patent No. 945,931.

[SEAL] "disks for lt is hereby certified that in Letters Patent No. 945,931, granted January 11 of Beloit, Wisconsin, for an improvement in Page 1, line 43, for the word compose,

quality, a result not readily obtainable by the' processes ployed.

lt. will be observedthat a disk made in accordance with our invention requires, no cuttingor trimming.

Tilting the grains of abrasive material places the great. majority of them in position to do effective work.

le claim as our invention:

1. The process of producin grinding facing the sidesof te disks of disk grinders, which consists inthoroughly mixing a bond and a granular abrasive material, applying a thin coat of cement to a backing sheet, placing said mixture upon the coated surface of said backing sheet, placing the grains with their cutting edges in cutting position, and drying.

Q. The process of producing grinding disks for facing the sides of the disks of disk grinders, which consists in mixin a bond and a granular abrasive material, applyin a thin coat of cement to a backing sheet, p :icing said mixture upon the coated surface of said backing sheet, rolliner the mixture into a layer of uniform thickness, tilting the grains to dispose their cutting edges in cutting position, and drying. l

3. The ste in the process of producing grinding dis s for facing the sides of the disks of disk grinders, which consists in tilting the grains after they have been deposited, so that their cutting edges are directed toward the face of the disk.

FREDERICK GARDNER. FREDERIC E. GARDNER. Witnesses:

' T. D. WOOLSEY,

F. F. LiviiaMonn.

and certainly heretofore em- 1910,l upon the application of Frederick N. Gardner and Frederic E. Gardner,

Disks errors appear in the printed specification requiring correction as follows:

read comprise; same page, line 4.4, the

should be canceled; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case Signed and sealed this 31st day of March, D., 1914.

J. T. NEWTON,

Acting ommesoner of Patents.

Processes for Producing Grindinglt is hereby certified that in Letters Patent No. 945,931, granted January 1L 1910, upon the application of Frederick N. Gardner and Frederic E. Gardner,

of Beloit, Wisconsin., for an improvement in Processes for Producing Grinding- Dieks errors appear in the printed specification requiring correction as follows:

Page l, line 43. for thc word composc, read comprise; same page, linc 44, the

word in" should be canceled; and that the said Letters Patent should bo read with these corrections therein that the same muy conform to thc record of the case in the Patent. Olliro.

Signed and sealed this 31st day of March, A. D., 1914.

[SEAL] J. T. NEWTON,

Acting Commissioner of Patents. 

